Rotary pump



Sept. 23, 1952 F. M. KIRKPATRICK ROTARY PUMP 5 Sheet s-Sheet 1 Filed Nov. 26, 1949 Fig.1.

Inventor Plogd M. Kirkpatrick, b flww/i.

His Attorneg.

Sept. 23, 1952 F. M. KIRKPATRICK ROTARY PUMP 5 sheets-sheet 2 Filed Nov. 26, 1949 Inventor: Pl 055d M. Ki'r k p a'Erick,

MK His Attorneg.

Sept. 23, 1952 F. M. KIRKPATRICK ROTARY PUMP S'Sheets-Sheet 3 Filed NOV. 26, 1949 Inventor:

Sept. 23, 1952 F. M. KIRKPATRICK ROTARY PUMP 5 Sheets-Sheet 4 Filed Nov. 26, 1949 1 was I 32 32 El -as FiglS.

Inventor: Floyd M. Kirkpatrick,

His Attorney.

Sept. 23, 1952 F. M. KIRKPATRICK Q ROTARY PUMP 5 Sheets-Sheet 5 Filed NOV. 26, 1949 Fig. 24.

, Inventor Floyd M. Kirkpatrick, by aka... 1M

His Attorneg.

Patented Sept. 23, 1952 ROTARY PUMP Floyd M. Kirkpatrick, Erie, Pa., assignor to General Electric Company, a corporation of New York Application November 26, 1949, Serial No. 129,644

My invention relates to pumps and more particularly to pumps of the rotary type.

It is an object of my invention to provide an improved pump having parts symmetrically arranged to give a minimum dynamic unbalance.

It is another object of my invention to provide a pump including an improved arrangement for minimizing surges.

Further objects and advantages of my invention will become apparent as the following description proceeds and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming part of this specification.

In carrying out the objects of my invention a rotor having a spherical surface is arranged for rotation within a housing having a complementary spherical surface. The rotor is provided with two intersecting grooves each of which has a piston segment positioned therein. The piston segments are prevented from rotating with the rotor, but are permitted to oscillate laterally. These segments are arranged so that each blocks one of the grooves while the other effects compression of the fluid within the groove against the blocking segment.

For a better understanding of my invention reference may be had to the accompanying drawings in which Fig. 1 is a view partly broken away of a refrigerating unit including a compressor embodying my invention; Fig. 2 is an enlarged plan view, partly broken away, of the compressor shown in Fig. 1; Fig. 3 is an enlarged end view partly in section of the compressor shown in Fig. 1; Fig. 4 is an exploded view of the compressor; Figs. 5 through 12 are views of the rotor and parts associated therewith in different positions of the rotor; Figs. 13 through 20 show developed views of the rotor and its associated parts in positions of the rotor corresponding to those shown in Figs. 5 through 12, respectively; Fig 21 is a sectional view of a modified assembly arrangement; Fig. 22 is an end view of the assembly shown in Fig. 21; Fig. 23 is a plan view, partially broken away, of a modified form of myinvention; and

Fig. 24 is a partial view taken alon the lines 24-24 in Fig. 23.

In thefollowing description. the pump is described in connection with its application as a compressor in a refrigerating apparatus but it will be apparent that it may be utilized in many other applications where pumping of fluid is required. Referring now to Fig. 1, there is shown a hermetically sealed case I within which is mounted a compressor 2. The compressor is positioned within the housing by rings 3 and 4 which fit within grooves in the case I and engage opposite faces of the compressor 2. The compressor is driven in any suitabl manner as by an electric motor (not shown) incorporated within the 20 Claims. (Cl. 230-137) case I and connected to the compressor through a drive shaft 5. Compressed refrigerant is discharged from the compressor through conduits 6 and 1 into a common conduit 3 from which it is circulated through the refrigerating system (not shown). Vaporized refrigerantis returned from the refrigerating system through a conduit 9 which discharges the refrigerant into the interior of the case i. Vaporized refrigerant within the case I is taken into the compressor through inlet conduits l0 and II, the open ends of which are positioned above the level l2 of any liquid refrigerant or oil within the case I.

Referring now to Figs. 2, 3, and 4 it can be seen that the compressor is driven through the shaft 5 which is supported within a bearing l3. The compressor includes a housing I4 which is composed of two complementary parts l5 and I6. The inner surface of each of the housing parts !5 and It is curved, as indicated at I! and I8, respectively so that when the two parts are assembled a spherical surface, forming a spherical chamber, is provided within the interior of the housing. In the form shown the housing parts are of such width that the ends of the sphere formed by the inner surfaces thereof are truncated. However, if desired, a housing could be enlarged and the inner surfaces of the parts [5 and N5 continued to provide a substantially complete sphere. The housing parts l5 and 16 are held in sealing engagement by devices such as screws l9 which pass through bores 20 in the upper housing part [5 and are arranged in threaded engagement with threaded openings 2| in the housing part It.

A rotor 22 is provided within the housing, the rotor being driven by the shaft 5. The outer surface of this rotor is curved to provide a generally spherical surface having the same radius of curvature asthe inner surface of the housing so as to rotate smoothly in engagement therewith. In the form shown the rotor is truncated, providing flat faces 23 and 24, and oscillation of the axis of rotation of the rotor is resisted by an arcuate ring 25 which fits within a groove 26 in the housing and engages the face 24 of the rotor. However, it will be apparent that, if desired, the rotor could be made in the form of a substantially complete sphere or ball instead of the truncated form shown. The bearing [3 may, if desired, be formed in two halves each integral with one of the two parts ofthe housing l4. Since the hearing I 3 maintains the axis of rotation of the rotor fixed, the arcuate ring 25 may be omitted, if desired. I

The rotor is provided with two circumferential grooves 21 and 28. These grooves intersect each other at diametrically opposite points of the rotor, one such intersection being indicated at 29. These grooves are inclined at-equal angles with respect to a plane perpendicular to the axis of the rotation of the rotor and extending through the two points of intersection of the grooves 2'1 and 28. In order to effect pumping of fluid a piston segment 35 is positioned within the groove 27 and a similar piston segment 3| is positioned within the groove 28. The outer spherical-sur faces Silo and Sla of the piston segments 35 and.

3! respectively are in line-with the spherical surface of the rotor 22 and hence are-in engage-- ment with the spherical surface of the housing M. Each of these piston segments is in the form of a semi-circular or half-annular section extending on a great circle of the rotor 2-2 sub stantially half the circumference thereof. To effect pumping: offluid? by the. compressor it is necessary: to restrain thepiston segments as and 3| against rotation with the rotor while still permitting lateral oscillation of these segments durihgsuohuotation of the rotor. This is accom plislied= by providing a pin= or projection on each of thepistom segments pivotally engaging a block which isslidably positioned within a transverse slot or recess-in thehousing M Thus, the piston segment 35- includes a; cylindrical projection or pi'n 32 which pivotally engages a sliding block 32 Thebloci: 32 is slidably positioned within a recess 33 formed in' the housing part l5 adjacent the r-otor 22 thesliding block 32 being substant'iall'y the same widthas the width of the recess 33. similarprojection or'pin 3e'isprovided" onthe' piston segment 31- and this pin 3'4' pivotall'y engage-ea sliding block 3?. The sliding hlocii'l St is positioned ina recess 3& formed in the lower housing part i5 adjacent the rotor 22 and the width of the block 34 is substantially the'same-as the width or'the recess 35. Toiacilitate oscillation ofthe piston segments the bottomsoflthe-groovesZT and 2 8 are formed-as part of thesurface of a sphere concentric with the surface of therotor 22', as indicated at 27- and 2 8", respectively, and theacljacent faces of the pistoirsegments are formed with the same curvatureasathebottoms of'the grooves 21 and28.

Two additional transverse recesses 36* and 37 are provided-in the housing I! adjacent the rotor 22. Eaclr ofthe transverse recesses 33, 35, 3'6, and 3 7 is provided for conducting fluid either to or from the interior of thecompressor, and for this purpose each of the recesses is of sufiicient length to extend in communication with one or theoth'er of the grooves 21, 28 at the point where the grooveis the greatest distance from the perpendicular plane through the intersections of the-grooves, for example, asindicated at 38. The recesses 3'6- and 31' are connected through passages 39 and 46-, respectively, in communication with the inlet conduits H and [-0, respectively. Conversely, the r-ecesses 3'3 and 35 are connected throughpassages 4 and 42:, respectively, in the housing ilr communication with the discharge conduits 6 and 1' respectively.

The construction and operation of the compressor can lce understood more clearl'y by referring Figs. 5 throug h. 1 2; which show the positions or". the various parts associated with the rotor in" diiteren't successive positions-of therotor, a-n'di to' the corresponding development views shown in Figs- 1 3 through respectively. The successive positions shown in Figs. 5 through- 12-- and' Figs. 13 through 20 differ by a 45 rotation of the-rotor 22. For convenience: in description, the transverse recesses 33 and 36 have been superimposed in dotted lines inFi'gs'. 5 through 1-2, inclusive, and transverse recesses 33; 35, 36

and 31 have been similarly indicated in Figs. 13 through 20, inclusive. The direction of rotation of the rotor 22 is indicated by the arrows. Starting with-Fig. 5, wherein the rotor occupies a posi tion corresponding to the position shown in Fig. 2,- Figs. 5 through 12, inclusive, show the positionof the various associated parts at 45 intervals throughout one revolution of the rotor. A 45 rotation of the rotor 22 from the crossover position of the piston segments 3D, 31 shown in Fig. 5 to the position shown in Fig. 6 causes a lateral shifting. of the piston segments and also a rotational movement of the rotor 22 relative to thepiston segments since the segments are restrained against rotation by the pins 32, 34 and blocks 32" andt l. An additional 45 turn of the rotor oausesashifting of theparts to the position-shown in Fig. 'l. A feature'of my inven tion is that each of the piston segments ac, 3i

simultaneously effects a pumping of fluid fromthe' groove in. which it is positioned and blocks the other groove at one of the intersections so as to act as a, barrier against. which the other piston segment efiects compression of fluid.

. Further, theblocking segment divides. the blocked: groove; into two portions, into one of which fluid:

isrtaken and from the other of which fluid: is discharged during the relative-1 movement of the segments caused by. rotation of the rotor; This can be seen by referring, for example, to Fig. 7

whereinithe piston segment 3!)? blocks the groove 2-8 as shownat 4-3 and. the piston segment 3! blocks". the groovev 21'.- as indicated atzM'. the movement from the position shown in Fig. 6. to: that. shown. in Fig. 7 the distance between an end 55 of the piston segment 39 and the" blocking face or side 44 of. the piston segment 3! increases and fluid is therefore drawn into this portion. of. the groove. 21 through the inlet conduit ill, the inlet passage 39 and the recess 36. Simultaneously, the groove 23 has moved relative to the piston segment 3 which is positioned within the groove: 28 so that the length of the. groove ESbetween an end 46 of the piston.

segment 1 and the blocking face or side 43' of the pistonsegment 3Z1 is decreasing; thereby resulting in acompression of fluid in this portion of the groove 28 and discharge of the fluid through the recess 33", the exhaust passage. 41,

1 and the conduit 62 Thisaction continues progressively through theposition shown in- Fig. 8

until the piston segments 36 and 31' reach the At this point Similarly, the" intake of fluid into the groove 21' between the end'dia of the piston segment 38 and the-blocking face M of thepiston segment: 31. has:

been completed.

It'wlll be noted that the transverse inlet recess 36 in the housing is spaced from the transverse discharge recess 33 by a distance: indicated. at 41. Similarly, the diametrically opposite pair. of

inlettand: discharge recesses 3'1 and 35, respec:--

tively; are circumf'erentially spaced from each other. by an amount indicated at. 48 in Fig. 3. The ends of the. pistonsegments 36;, 3t are positionediadjacent the spaces 41, 48- and move transversely within the area. encompassed by the:

spaces 4?, 48. Thus; the ends 45;. 46- of the piston segments. 39,. 31, respectively, move laterally adjacent the; space 41. Similarly, the opposite end. 4920f the piston segment 30' and the opposite end 50 of the: piston segment 3| move adjacent During.

the space 48 between inlet recess 31 and discharge recess 35. Itcan be seen, therefore, that the ends of the piston segments project beyond the transverse passages into the area therebetween and the piston segments thus block communication between the spaced inlet and discharge recesses except for a small amount at the exact point of crossover illustrated in Figs. 2, 5, and 9. The arranging of the ends. of the piston segments so that each extends beyond a transverse recess into the area between adjacent transverse inlet and discharge recesses also blocks communication between the grooves 21 and 28 through the recesses. Thus, referring to Fig. '7, for example, the piston segment 30 overlaps transverse recess 33 and its end 45 projects into the space 41. Communication from recess 33 is, therefore, limited to the groove 28 and communication between the recess 33 and the groove 21 and between the rooves 2! and 28 through the recess 33 is blocked by the end .portion of the piston segment 30. Similarly, communication between transverse recess 36 and groove 28 is blocked by the overlapping end 46 of the piston segment 3| which extends beyond the recess 36 and into the space 41 between recesses 33 and 36, and communication between the grooves 27, 28 through the recess 36 is also blocked. Communication from the recess 33 is therefore limited to the groove 21.

The adjacent ends of the piston segments 30, 3| are shaped so that these ends are enabled to pass closely adjacent each other at both the crossover points shown in Figs. 2 and 5 and the opposite crossover point illustrated in Fig. 9. Referring, for example, to the end 45 of the piston segment 30 it can be seen that this end is shaped to provide two inclined surfaces 5|, 52 meeting at an apex 53. The inclined surface 5| makes an angle with a side or face 54 of the piston segment 30 which deviates from a right angle by an amount equal to the angle which each of the grooves 27, 28 makes with a plane extending through the interesection 29 of the concentric grooves 21, 28 and also through the diametrically opposite intersection of these grooves perpendicular to the axis of the rotor. The inclined surface 52 makes the same angle with the opposite side or face 43 of the piston segment 30. The adjacent end 46 of the piston segment 3| similarly includes inclined surfaces 55 and 56 meeting at an apex 51. These surfaces make the same angle with sides or faces 58 and 44, respectively, of the piston segment 3| as the inclined surfaces 5| and 52 do with the sides 54 and 43, respectively, of the piston segment 30. The opposite ends of the piston segments 30, 3| are shaped in the same manner. As best illustrated in the crossover positions shown in Figs. 2, 5, and 9 this particular shape of the end of the piston segments enables the piston segments 30, 3| to move laterally past each other at both the crossover points with the ends positioned closely adjacent each other. Thus, at the crossover point shown in Figs. 2 and 5 the inclined surfaces 5| and 56 of the ends of the piston segments 3D and 3|, respectively, are substantially parallel to each other and are thereby enabled to move past each other while still positioned closely adjacent each other. Similarly, in the opposite crossover position shown in Fig. 9 the inclined surfaces 52 and 55 of the piston segments 30 and 3|, respectively, are disposed substantially parallel to each other and are similarly enabled to move past each other while still being maintained closely adjacent. eachv other. In order to minimize leakage at the crossover points shown in Figs. 2, 5, and 9, a check valve 8a is placed in the discharge conduit 8, as shown in Fig. 1.. To further reduce leakage twosuch valves may be employed closer to the compressor; one in each of the discharge conduits 6 and 1.

From the crossover position shown in Fig. ,9 the various parts assume, at successive 45 intervals in the rotation of the rotor, the positions shown in Figs. 10, 11, and 12. An additional 45 rotationof the rotor beyond the position shown in Fig. 12 returns the parts to the original position shown in Figs. 2 and 5. Referring to Figs.v

10, 11, and 12, it can be seen that the portion of the groove 21 between the end 45 of thepiston segment 30 and the blocking, face or side, 58'ofv the piston segment 3| gradually increases, vaporized refrigerant thereby being drawninto'this increasing space from the case through the inlet conduit the passage 39, and the transverse inlet recess 36. Similarly, the space between the end 46 of the piston segment 3| and the blocking face or side 54 of the piston segment 30 progressively decreases in size, compression of the vaporized refrigerant within the space between the end 46 of the piston segment 3| and the blocking face 54 being efiected. This compressed refrigerant is discharged through the transverse discharge recess 33, the passage,

4|, and the conduits 6 and 8. When the rotor has moved to the point where the parts are in positions as shown in Figs. 2 and 5 the length of the groove 27 between the end 45 of the piston segment 36 and the blocking face 53 of the piston segment 3| has reached a maximum, completing the intake of fluid to the groove 21, and the compressing and discharging of refrigerant from the groove 28 between the end 46 of the piston segment 3| and the blocking face 54 of the piston segment 30 has also been completed.

The representations in Fig. 2 and in Figs. 5 through 12, inclusive, illustrate the movement of the rotor and of the piston segments with reference to one transverse inlet recess and one transverse discharge recess. As illustrated in Fig. 3, the compressor includes two diametrically opposite inlet recesses 36 and 31 and two diametrically opposite discharge recesses 33 and 35. It will be apparent, therefore, that while the movement of the rotor is eifecting an intake of fluid through the passage associated with the recess 36 and a discharge of fluid through the passage associated with the recess 33, a simultaneous intake and discharge is being effected at the opposite side of the rotor through the recesses 31 and 35, respectively. In order to illustrate the overall operation more clearly, the developed views shown in Figs. 13 through 20, inclusive, have been included. These views correspond to those shown in Figs. 5 through 12, inclusive; thus, in Fig. 13 the parts are shown in the same relative positions as in Fig. 5, in Fig. 14 in the same relative position as in Fig. 6, and in Fig. 15 in the same relative positions as in Fig. 7, etc. The same numerals have been. applied to corresponding parts in these two groups of figures. For convenience, each developed view has been illustrated directly below the corresponding view of the group embracing Figs. 5 through 12, inclusive. To illustrate the operation more clearly the transverse inlet recesses 36 and 31 and the transverse discharge recesses 33 and 35 have been superimposed in dotted lines in the developed views shown in Figs. 13 through 20', inclusive.

'Referring'to Fig. 13 itlwill benoted that the ends of the piston segmentes are both. at the crossover point. It: can be seen further by reference: to this. figure that the groove 21. is in communication wit-h the transverse inlet recess.

36' and with the transverse discharge recess 35. The groove 28 is in. communication with the transverse inlet-recess 31' and-the transverse discharge recess 33; Referring now. to Fig. 14 wherein the rotor has moved 45 degrees in the direction indicated by thearrow, it canbe seen that the groove 21 is divided by the piston segment' 31 into two parts 59 and 60, the portion 59. of the groove 2-! being in communication with the inlet recess -36 and the portion 68 of the groove 21 being in communication with the discharge recess 35.. At the same time the piston segment 30 divides the groove 28- into two portions 61 and 62', the portion 61- of the groove 28 being in communication with the discharge recess 33 and the portion 62 of the groove 28 being in communication with the inlet recess 3-1. Thus, the motion of the rotor in moving from the positionshown in Fig. 13 to the position shown in Fig. 14 has eifected the simultaneous intake of fluid through conduit H, passage 39, and the recess 38' to the portion '59 of the groove 21 and-the discharge of compressed fluid from the portion 69 of the groove 21 through the exhaust recess 35 and thence through passage 42 and conduits 1 and 8. At the same time fluid is taken-into the portion 62 of the groove 28 through the conduit 10, passage 40- and inlet recess31, and fluid is discharged from the per-- tionfil of the groove 28 through'thedischarge recess 33 and thence through passage 4| and conduits 6 and 8.

The progressive action can be followed further by a comparison of the positions of various parts in Figs. 14, 15, and 16. By this comparison it can be seen that the portion 59- of the groove 21 becomes progressively larger effecting a cont-inuing intake of fluid while the portion 60- of the groove 21 becomes progressively smaller continuing-the discharge of fluid through the dis-- charge recess 35; Simultaneously theportion- 62' ofthe g v zs' rogressivel'y enlarges continuing to receive fluid therein and the portion Gldecreases thereby causing a further discharge of fluid from the-portion Bl oft-he groovez filthroughthe discharge recess-33':

A'comparison of Figs; 14-, 15 and 16 illustrates that the discharge of the fluid from the'portion 61 of the groove 23 iseffected by relative move-'- ment between the end it of the piston segment 31- and the blocking face 4-3 of the piston seg ment30-which blocks the groove 21' at one intersection 63- of the grooves 21 and-2'8; Similarly, the discharge of the fluid fromthe portion: Gii of the groove 21 is efiectedby relative movement of an end 640i the piston segment 36 and-bloch-- ing face 58'of the piston segment 31 at the inter section 29' of the grooves 21 and 283. The intersections 29 and 63 of the grooves-2'1 and 283. are at diametrically opposite points'iof the rotor 22; Similarly, the progressively enlarging: portion 59 of the. groove 2:1 is blocked atonetend" by the end 45. of the piston segment .30.:and. at the other end by the face: M of the. piston'segment.

3|, relative. movement of the blocking face 4'4:

of. the piston. segment. 3| andthe. endi 4510f the piston segment 30 resultinglirr a; progressive" in crease in the size of. the portion Enduring-this. period of rotation of the rotor;. The progres. sively enlarging portion 62 of the groove: 28: is.

; the piston segment 31.

I 21 and. they portion 62 of the groove 28 have:

reached. their maximum. size, completing. the 'in-- take of fluid into these portions. of: the grooves. Similarly,zthe exhausting of. fluid fromthe portion 6030f. the groove 21' and the portion 61 of. the groove-.28 has been. completed.

Movement of the: rotor beyond the point 11- lustrated' in Fig. 17' initiates acompression and; dischargegof the fluid: which during. the previous. half revolution of. the rotor. has been taken into:-

'- the portion 59 of the, grooveZl and the portion 62' of thegroove 28'. This action is illustrated. progressively in Figs. 18; 19, and 20. Referringto these figures it can beseen that. the movement ofv the rotor through the successive 45 degree 1 position illustrated effects a progressive reduction in the size of the portion 62 of the groove 28 through the relative movement of the blocking face 54 of the piston segment. 30 and the. end 46 of the piston segment 3!. This effects a discharge of fluid through the discharge re-- cess 33. Similarly, the rotation of therotor effects a reduction in the size of the portion 59 of the groove 21* through the relative movement ofthe blockingface 4dof the piston seg-- ment 3-! and the end 64 of the piston segment" grooves 2.1 and 2B..through inlet recesses-36. and

3],..respectively. The enlarging of. the portion 68 of the groove 21 iseffected by the-relative movement, between blocking face 58 of the piston segment 3 i: and the end 45 of the piston seg ment-tfl. Similarly, a progressive enlarging; of the portion- 61- of the groove 28 is effected by the relativemovement between the blocking face i3lof1 the piston segment 38" and the end; 63 of The fluid taken into; the portion-tu of the-groove 2-1' and the portion 61 of the groove 28; during the half revolution of the rotor illustratedin Figs. 1-8, 19; and: 20 is; compressed and discharged therefrom during the haltrevolution ofthe rotor illustrated in Figs. 1-4, 1-5, and 1e.

Itwill be apparent, therefore, that they intake and discharge-of fluid from each ofthe grooves occurs; twice per revolution of the rotor, fluid being taken into one portion of the groove and. simultaneously discharged from another portion of the groove during each half revolution of therotor. Therev are, therefore, four compression pulses per revolution of the rotor and the distributi'onof the compressingefiectinto four such pulses reduces the surge considerably below that. n: a. reciprocating. compressor, for example, having only one compression. pulse per revolution. Moreover, the construction described provides a smooth acceleration: and deceleration of the sag-- ments 30 and 3| which act both as pistons and as valves.

In Figs. 21 and 22 there is shown a modified arrangement for assembling the parts of the pump. This modified form includes a housin composed of two parts 66 and 6'! which cooperate to provide a generally spherical chamber 68 for receiving the spherical rotor (not shown). In this form, in lieu of employing devices such as thescrews [9 for holding the two parts of the housing in assembled position, the parts 66 and 67, corresponding to the parts 15 and I6, respectively, of the form previously described, are snugly received within a hollow cylindrical housing 69. The cylindrical housing 69 includes a shoulder 10 which spaces the rotor from the face H of one end of the housing. An opening 12 is provided in this end of the housing 69 and afiords a bearing surface 13 for the driving shaft (not shown). The bearing surface 13 maintains the driving shaft and the rotor in proper alignment within the chamber 68. A resilient arcuate ring 14, adapted to be received within a groove 15, is employed for maintaining the parts 66 and 61 in assembled relationship against the shoulder 10. A recess 16 is provided in the housing part 66 and a pin 11 mounted in the cylindrical housing 69 projects into the recess to prevent rotation of the housing formed by parts 66 and 61. The overall assembly illustrated in Figs. 21 and 22 may be assembled within a case similar to the case I' shown in Fig. 1.

In Figs. 23 and 24 there is illustrated a modified form of my invention utilizing a different arrangement for permitting oscillation or lateral movement of the piston segments and at the same time preventing rotation of the piston segments with the rotor. The same numerals have been used to designate corresponding parts in Figs. 23 and 24 and in the preceding figures. As in the form shown in Figs. 2, 3, and 4, the modification illustrated in Figs. 23 and 24 includes a two-part housing having an upper part 18 and a lower part 19, corresponding to the parts l and I6 respectively. Arcuate grooves are provided in the face of housing part 18, one such groove being indicated at 80 in Fig. 24, and complementary arcuate grooves are provided in the abutting face of the lower housing part 19, one such groove being indicated at 8| in Fig.

24. In the assembled position of the parts 18, 19 these grooves cooperate to form diametrically opposite recesses adjacent the surface of the rotor 22, one such recess being indicated at 82 in Fig. 24. An arcuate segment or key 83 is positioned in the recess 82 and a corresponding arcuate segment or key 84 is positioned in the diametrically opposite recess. The recesses permit oscillation of the keys 83, 84 laterally of 1 the rotor but prevent rotation of the keys with the rotor. In order to prevent rotation of piston segments 30' and 3| with the rotor while at the same time permitting oscillation of these piston segments, the piston segments 30', 3| are pivotally connected to the keys 83, 84 by pins 85 and 86, respectively. During rotation of the rotor each of the keys 83, 84 is free to move laterally in its respective recess, thus permitting oscillation of the piston segments 30', 3|. The necessary pivoting of the piston segments 30, 3| is permitted by the pivotal connection between these piston segments and the keys 83, 84 provided by the pins 85, 86.

Operation of the modified form shown in Figs. 23 and 24 with respect to the pumping of fluid 10 is the same as that of the form shown in Figs. 1, 2, 3, and 4, and the detailed description and analysis of the operation set forth in discussing Figs. 5 through 20, inclusive, is equally applicable to the modified form illustrated in Figs. 23 and 24. 1

While I have shown and described specific embodiments of my invention, I do notdesire my invention to be limited to the particular constructions shown and described, and I intend bv the appended claims to cover all'modifications within the spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States, is:

l. A pump comprising a. housing having a spherical chamber therein, a rotor within said chamber, said rotor having a spherical surface arranged to engage the surface of said chamber, said rotor having a pair of circumferential grooves formed in said spherical surface thereof, said grooves intersecting each other at two diametrically opposite points, a semicircular piston segment positioned in each of said grooves, means for maintaining said piston segments against rotation with said rotor while permitting lateral oscillation of said segments, and an inlet recess and a discharge recess within said housing adjacent said spherical surface of said rotor communicating with each of said grooves, both of said recesses extending transversely with respect to said grooves, said recesses being circumferentially spaced from each other and being disposed on opposite sides of a plane extending between the ends of said segments and along the axis of said rotor.

2. A pump comprising a housing having a spherical chamber therein, a'rotor' within said chamber, said rotor having a spherical surface arranged to contact the surface of said chamber, said rotor having a pair of circumferential grooves formed in said spherical surface thereof, said grooves intersecting each other at two diametrically opposite points, a semicircular piston segment positioned in each of said grooves, an inlet recess and a discharge recess within said housing adjacent said spherical surface of said rotor communicating with each of said grooves, both of said recesses extending transversely with respect to said grooves, said recesses being circumferentially spaced from each other and being disposed on opposite sides of the plane extending between the ends of said segments and along the axis of said rotor, and means engaging said housing and said piston segments for maintaining said piston segments against rotation with said rotor and permitting lateral oscillation of said piston segments.

3. A pump comprising a housing having a spherical chamber therein, a rotor within said chamber, said rotor having a spherical surface arranged to engage the surface of said chamber, said rotor having a pair of circumferential grooves formed in said spherical surface thereof, said grooves intersecting each other at two diametrically opposite points, a semicircular piston segment positioned in each of said grooves, means for maintaining said piston segments against rotation with said rotor while permitting lateral oscillation of said segments, an inlet recess within said housing communicating with one of said grooves, a diametrically opposite inlet recess within said housing communicating with the other of said grooves, a, discharge recess within said housing adjacent said spherical surface of said rotor communicating with said one of said ,zaerneaa grooves, :and a diametrically opposite discharge recess within said housing communicating with said other of said grooves, lialllof said rece'ssesextending itransversely iwith;respect to said grooves, eacho'f said inlet recesses being circumferentially spaced from the corresponding one .of said discharge recesses and being disposed on the .opposite'side from said corresponding one :of .said discharge recesses with respect to a plane extending between the ;ends of 'said segments and along'the axisof said rotonl V 4. .A pump comprising a-housing having a spherical chamber .therein,ta rotor within .said chambensaidrotor havinga spherical surface arranged to engage 'theJsurface of said chamber, .said. rotor having a pair of circumferential grooves formed in said spherical surface thereof, vsaid grooves intersecting each other at two diaimetrically opposite points, asemicircular piston segment positioned ineach of .said grooves,imeans formaintainingsaid pistonsegments against rotation, said segments beingarranged forlateral oscillation during rotation of saidrotor, an inlet recess and a discharge recess within said housing adjacent said l spherical surface of said rotor communicating with each of said grooves, both of said recesses extending transversely with respect to said grooves,-said recesses being circumferentially spaced from each other and beingdisposed on opposite sides of .a plane extending between the ends of said segments and along the axis of said rotor, the piston segment in-one of said grooves extending across said other of said grooves at one intersection of said grooves to block fiow of fluid along said other of said grooves, the piston segment in said other of said igrooves'extending acrosssaid one of said grooves at theother intersection of said grooves to block flow of "fluid along said one of said grooves.

.5. A pump comprising a housing having a spherical chamber-therein, :a rotor within said chamber, said rotorshaving -a spherical surface arranged to contact the .surfaceiof said-chamber, said rotor having a pair of circumferential grooves formed in said-sphericalsurface thereof, said grooves intersecting each other at two diametrically opposite points, a semicircular piston segment positioned in each of said grooves, an inlet recess within said housing adjacent said spherical surface of said "rotor communicating with one of said grooves, a discharge recess within said housingadjacent said spherical surface ofsaid rotor and spaced circumferentially from said inlet recess and communicating with the other of said grooves, both :of said recesses extending transversely'with respect to said grooves, and means for maintaining saidpiston segments against rotation with saidrotorwhile permitting lateral oscillation of said segments, said means maintaining the adjacent ends'of said pistonsegmerits in the area between said inlet recess and said discharge recess.

6. A pump comprising a housing having a spherical chamber therein,:a rotor Within said chamber, said rotor having a, spherical surface arranged to contact the surface of said chamher, said rotor having a pair of circumferential grooves formed in said spherical'surface thereof, said grooves intersecting each other .at two diametrically opposite points, a semicircular piston segment positioned each of said grooves, two diametrically opposite inlet recesses within said housing adjacent said spherical surface of said rotor, two diametrically opposite discharge recesses within said housing adjacent "said spheri- 12 :cal surface of saidrotor, all lofssaidmecesses sextending transversely with respect to saidigrooves, :one of :said inlet recesses and .one of said hischarge recesses communicating :with :each 'of :said vgrooves, :each 'of said discharge :recesses being circumferentially :spaced .from a corresponding one of saidinlet .r.ecesses,;means engaging one of .said ;piston segments and extending into one-of said recesses for maintaining said one :of :said piston segments :against rotation with said :rotor while ;permitting'1ateral oscillation of said one of said piston segments, and means wengagingthe otherof said piston segments-and extending-into ,another of said recesses ;for maintaining said :other :of said piston segments against rotation with saidvrotor While permitting lateral oscilla tion of said other of said piston .segmentsthe Iadjacent ends of Said piston segments being maintained by said last two means in the area between corresponding spaced inlet and discharge recesses.

7.111 1 131111113 comprising a housing having a spherical chamber therein, a rotor within :said chamber, said rotor having a sphericalsurface arranged to contact the surface of said-chamber, .said =rotor having a pair of circumferential grooves formed in said-spherical 'surface'thereof, said grooves intersecting each other at two 1diametrically opposite points, a semicircular piston segment positioned iii-each of said grooves, two diametrically opposite inlet recesses 'within said housing adjacent said spherical surface of said .rotor, two diametrically opposite discharge zrecesses within said housing adjacent said sphericalsurface of said rotor, ,all of saidrecesses 'extending transversely with respect to said grooves, one of saidirilet.recesses andlone of said discharge recesses communicating with each of said grooves, 1 each of saiddischargerecesses being circumferentially spaced (from a corresponding one of -said-inlet recesses, a block slidably disposed in one :of said transverse recesses, .a :pin for pivotally connecting one of said piston segments and said block-for maintaining said oneof said .piston segments against rotation with said rotor while permitting lateral oscillation of said'one of said piston segments, a second block sli'dably disposed in another of said recesses, and a second pin pivotally connecting the other of said piston segments and said second block for'maintainingsaid other of said piston segments against rotation with'said rotor while permitting lateral oscilla- .tion of said other of :said piston segments, the adjacent ends of :said piston segments being maintained by saidlast two means in the area between corresponding spaced inlet and discharge recesses. V

-8. A pump comprising a 'housinghaving a spherical chamber therein, a rotor within said chamber, said rotor having a spherical :surface arranged to'contact the surface of said chamber, said rotor having a pair of circumferential grooves formed insaid spherical surface thereof, said grooves intersecting each otheratitwo diametrically opposite points and :making vequal angles with a plane extending :along the :axisof rotation of said rotor, a semicircular piston seg- 'ment positioned in each of 'saidgrooves, each of said pistonsegments including two parallel elongated side walls, -two diametrically opposite inlet recesses within said'housing adjacentlsaid spheri'cal surface of said rotor, two diametrically opposite discharge recesseswithinisaid housing adjacentsaid spherical surface of said rotor, all of said recesses extending transversely with respect to said grooves, one of said inlet recesses and one of said discharge recesses communicating with each of said grooves, each of said discharge recesses being circumferentially spaced from a corresponding one of said inlet recesses, and means for maintaining said piston' segments against rotation with said rotor and for maintaining the adjacent ends of said piston segments in the area between corresponding spaced inlet and discharge recesses, the ends of said piston segments being formed of two inclined surfaces meeting at a central apex, said inclined surfaces making the same angle with said parallel side walls of said piston segments as the grooves make with the plane extending through the axis of rotation of said rotor whereby as the ends of said piston segments move past each other during lateral movement in either direction the adjacent inclined surfaces of said piston segments are in substantially parallel relationship making possible a minimum clearance between the ends of said piston segments.

9. A pump comprising a housing having a spherical chamber therein, a rotor Within said chamber, said rotor having a spherical surface arranged to engage the surface of said chamber, said rotor having a pair of circumferential grooves formed in said spherical surface of said rotor, said grooves intersecting each other at two diametrically opposite points, a first semicircular piston segment in one of said grooves, a second semicircular piston segment in the other of said grooves, means for maintaining said piston segments against rotation with said rotor while permitting lateral oscillation of said segments, an inlet recess and a discharge recess within said housing adjacent said spherical surface of said rotor communicating with each of said grooves, both of said recesses extending transversely with respect to said grooves, said recesses being circumferentially spaced from each other and being disposed on opposite sides of a plane extending between the ends of said segments and along the axis of said rotor, said first segment blocking said other of said grooves at one of said intersections of said grooves and simultaneously effecting compression fluid in said one of said grooves against said second segment, said second segment blocking said one of said grooves at the other of said intersections of said grooves and simultaneously effecting compression fluid in said other of said grooves against said first segment.

10. A pump comprising a housing having 'a spherical chamber therein, a rotor within said chamber, said rotor having a spherical surface arranged to engage the surface of said chamber, said rotor having a pair of circumferential grooves formed in said spherical surface of said rotor, said grooves intersecting each other at two diametrically opposite points, a first semicircular piston segment in one of said grooves, a second semicircular piston segment in the other of said grooves, means for maintaining said piston segments against rotation with said rotor while permitting lateral oscillation of said segments, and two diametrically opposite inlet recesses and two diametrically opposite discharge recesses within said housing adjacent said spherical surface of said rotor, one of said inlet recesses and one of said discharge recesses communicating with each of said grooves, all of said recesses extending transversely with respect to said grooves, each of said inlet recesses being circumferentially spaced from the corresponding one of said discharge re- I I cesses and being disposed on the opposite side from said corresponding one of said discharge recesses with respect to a plane extending between the ends of said segments and along the axis of said rotor, said first segment extending across the other of said grooves and. dividing said other of said grooves into a first portion communicating with one of said inlet recessesand a second portion communicating with one of said discharge recesses, said second segment extending across said one of said grooves and dividing said one of said grooves into a first portion communicating with the other of said inlet recesses and a second portion communicating with the other of said discharge recesses, rotation of said rotor causing relative movement of said segments to effect an increase in size of said first portions and a simultaneous reduction in size of said second portions whereby simultaneous intake and discharge of fluid is effected to and from each of said grooves.

11. A pump comprising a housing having a spherical chamber therein, a rotor within said chamber, said rotor having a, spherical surface arranged to engage the surface of said chamber, said rotor having a pair of circumferential grooves formed in said spherical surface of said rotor, said grooves intersecting each other at two diametrically opposite points, a first semicircular piston segment in one of said grooves, a second semicircular piston segment in the other of said grooves, means for maintaining said piston segments against rotation with said rotor while permitting lateral oscillation of said segments, and two diametrically opposite inlet recesses and two diametrically opposite discharge recesses within said housing adjacent said spherical surface of said rotor, one of said inlet recesses and one of said discharge recesses communicating with each of said grooves, each of said inlet recesses being circumferentially spaced from the corresponding one of said discharge recesses and being disposed on the opposite side from said corresponding one of said discharge recesses with respect to a plane extending between the ends of said segments and along the axis of said rotor, said first segment extending across the other of said grooves and dividing said other of said grooves into a first portion communicating with one of said inlet recesses and a second portion communicating with one of said discharge recesses, said second segment extending across said one of said grooves and dividing said one of said grooves into a first portion communicating with the other of said inlet recesses and a second portion communicating with the other of said discharge recesses, rotation of said rotor causing relative movement of said segments to effect an increase in size of said first portions and a simultaneous reduction in size of said second portions whereby simultaneous intake and discharge of fluid is effected to and from each of said grooves, said rotor effecting change in size of said first and second portions to a maximum and a minimum respectively during each half revolution whereby intake and discharge of fluid to and from each groove is effected twice per revolution of said rotor.

12. A pump comprising a housing having a spherical chamber therein. a rotor within said chamber, said rotor having a spherical surface arranged to engage the surface of said chamber, said rotor having a pair of circumferential grooves formed in said spherical surface of said rotor, said grooves intersecting each other at two :diametrically opposite points; a :firstsemicircular piston segment in zone of saidxgrooves, a second semicircular :piston segment in the other of :said grooves, means for -maintaining said piston'segments againstrotation withsaid rotor while per mittinglateral oscillation of said segments, and two diametrically opposite inlet recesses and two diametrically opposite dischargereccsses within said .housing adjacent said spherical surface of said rotor, one of said inletrecesses and one of said discharge recesses communicating with each of said grooves, each of said inlet recesses being circumferentially spaced from the corresponding one of said discharge recesses and being disposed on the opposite side from said corresponding one of said discharge recesses with-respect to a plane extending between the ends .of said segments and along the axis of said :rotor, said first segment :extendingacross the other of said grooves and dividing said other of said grooves into a first portion communicating with one of said inlet recesses and .a second portion communicating with one of said discharge recesses, said second segment extending across said one of'said-grooves and dividing said one of said grooves into a first portion communicating with the other of said inlet recesses and a second portion communicating with the other 'of said discharge recesses, one side of each ofsaid segments being disposed toward the portion .of each of c-said groovescornmunicating with one of said inlet recesses and the other side .of each of "said segments being disposed toward the portion of each of said grooves communicating with a discharge recess during onehalf revolutionof said rotor,-said one side of each of said segments "being disposed toward the portion of each of :said grooves cornmunicating with a discharge recess and said other side of each :of said segments being disposed toward the portion of .each of-said grooves communicating with :an inlet recess during the next half revolution of :said rotor.

'13-. A pump comprising .a housing having a spherical chamber therein, a rotor within said chamber, said rotor having a truncated spherical surface arranged to engage the surface of said chamber, said rotor having its axis of rotation perpendicular tothe faces 'of the truncated por- 'tions thereof, said rotor having a pair of circumferentialgroovesformed in said spherical surface of said rotor, said grooves intersecting each other at two diametrically opposite points, said grooves being inclined at equal angles with respect to a plane perpendicular to the axis of rotation of said rotor and extending through the intersections of said grooves, a semicircular piston segment positioned in each of said grooves, means formaintainingsaid piston segments against rotation with said rotor While permitting lateral oscillation of said segments, and an inlet recess and a discharge recess within said housing adjacent said spherical surface of said rotor communicating with each of said grooves, both of said recesses extending transversely with respect to said grooves, said recesses being circumferentially spaced from each other and-being disposed on opposite sides of a plane extending between the ends of said segments and along the axis of said rotor.

14.A pump comprising a, housing having a spherical chamber therein, a rotor within said chamber, said rotor having a truncated spherical surface arranged to engage the surface of said chamber, said rotor having its axisof rotation perpendicular to the faces of the'truncated portions thereof, ineans engaging said housing and the face of atleast one of said truncated portions of said rotor to'prevent oscillation ofthe axis of rotation of said rotor, said rotor having a pair recess and a discharge recess within said housing adjacent said sphericalsurface-of said-rotor communicating with each of said grooves, both of said recesses-extending transversely with rcspect to said grooves, said recesses being circumierentially spaced from each other and being disposed on opposite sides of a planeextending between the ends of said segments andalong the axis of said rotor.

'15. A pump comprising a housing having a spherical chamber therein, a rotor within said chamber, said rot-or having a spherical surface arranged to engage the surface of said chamber, said rotor having a pair of spherical grooves formed in said spherical surface of said rotor,

said grooves intersecting each otherat :two diametrically opposite points, said grooves -beinginclined at equal angles with respect to a plane perpendicular to the axis of rotation of said rotor and extending through the intersections of said grooves, a semicircular piston segment positioned each of said grooves, -means for maintaining said segments against rotation with said rotor while permitting lateral oscillationof-said segments, a pair of inlet recesses and a pair of discharge recesses within said housing adjacent said spherical surface of said rotor, all of said recesses extending transversely with respect to said grooves, each of said inlet recesses being circumferentially spaced from the corresponding one of said discharge recesses and being disposed on the opposite side from said corresponding one of said discharge recesses with respect to a plane extending between the ends of said segments and along the axis of said rotor, one of said inlet-recesses and one of said discharge recesses communicating with each of said grooves, each of said recesses being of suificient length to communicate with its respective groove throughout each revolution of said rotor.

16. A pump comprising a housing having a spherical chamber therein, a rotor within said chamber, said rotor having a spherical surface arranged to engage the surface of said chamber, said rotor having a pair of circumferential grooves formed in saidspherical surface thereof, said grooves intersecting each other at two diametrically opposite points, a semicircular piston segment positioned in each of said grooves, said housing having two key-receiving recesses therein adjacent said spherical surface of said rotor and extending transversely with respect to said grooves, two keys arranged for lateral oscillation within said housing, one of said keys being slidable in each of said key-receiving recesses, a pin for pivotally connecting each of saidkeys to one of said segments to prevent rotation of said segments with said rotor, and an inlet recess and a discharge recess within said housing adjacent said spherical surface of said rotor communi- 17 eating with each of said grooves, both of said last-named recesses extending transversely with respect to said grooves, said last-named recesses being circumferentially spaced from each other and being disposed on opposite sides of a plane extending between the ends of said segments an along the axis of said rotor.

17. A pump comprising a housing having a spherical chamber therein, a rotor within said chamber, said rotor having a spherical surface arranged to engage the surface of said chamber, said rotor having a pair of circumferential grooves formed in said spherical surface thereof, said grooves intersecting each other at two diametrically opposite points, a semicircular piston segment positioned in each of said grooves, said housing having two diametrically opposite keyreceiving recesses therein adjacent said spherical surface of said rotor and extending transversely with respect to saidgrooves, two diametrically opposite keys arranged for lateral oscillation within said housing, one of said keys being slidable in each of said key-receiving recesses, a pin for pivotally connecting each of said keys to a corresponding one of said segments to prevent rotation of said segments with said rotor, each of said pins engaging its corresponding key and corresponding segment substantially at the center of said corresponding key and said corresponding segment, and an inlet recess and a discharge recess within said housing adjacent said spherical surface of said rotor communicating with each of said grooves, both of said lastnamed recesses extending transversely with respect to said grooves, said last-named recesses being circumferentially spaced from each other and being disposed on opposite sides of a plane extending between the ends of said segments and along the axis of said rotor.

18. A pump comprising a housing having a spherical chamber therein, a rotor within said chamber, said rotor having a spherical surface arranged to engage the surface of said chamber, said rotor having a pair of circumferential grooves formed in said spherical surface thereof, said grooves intersecting each other at two diametrically opposite points, a semicircular piston segment positioned in each of said grooves, the bottom of each of said grooves having a spherical surface concentric with the surface of said rotor, the inner surface of each of said piston segments having a curvature corresponding to that of its respective groove, means for maintaining said piston segments against rotation with said rotor while permitting lateral oscillation of said segments thereof, and an inlet recess and a discharge recess within said housing adjacent said spherical surface of said rotor communicating with each of said grooves, both of said recesses extending transversely with respect to said grooves, said recesses being circumferentially spaced from each other and being disposed on opposite sides of a plane extending between the ends of said segments and along the axis of said rotor.

19. A pump comprising a housing having a spherical chamber therein, a rotor within said chamber, said rotor having a spherical surface arranged to contact the surface of said chamber, said rotor having a pair of circumferential grooves formed in said spherical surface thereof, said grooves intersecting each other at two diametrically opposite points, a semicircular piston segment positioned in each of said grooves. two

diametrically opposite inlet recesses within said housing, one of said inlet recesses communicating with each of said grooves, two diametrically opposite discharge recesses within said housing, one of said discharge recesses communicating with each of said grooves, all of said recesses extending transversely with respect to said grooves, each of said inlet recesses being spaced circumferentially from a corresponding one of said discharge recesses, and means maintaining said piston segments against rotation with said rotor while permitting lateral oscillation of said segments, said means maintaining one pair of adjacent ends of said segments in the space between one of said transverse inlet recesses and the corresponding one of said discharge recesses, said means maintaining the other pair of adjacent ends of said segments in the space between the other of said inlet recesses and the other of said discharge recesses, one of said segments having one end extending beyond said one of said inlet recesses and its other end extending beyond said other of said discharge recesses to block communication between said last-named recesses and one of said grooves, the other of said segments having one end extending beyond said other of said inlet recesses and its other end extending beyond said one of said discharge recesses to block communication between said lastnamed recesses and the other of said grooves.

20; A pump comprising a housing having a spherical chamber therein, a rotor within said chamber, said rotor having a spherical surface arranged to engage the surface of said chamber, said rotor having a pair of circumferential grooves formed in the spherical surface thereof, said grooves intersecting each other at diametrically opposite points, a first piston segment positioned in one of said grooves and extending substantially half the length of said one of said grooves, a second piston segment positioned in the other of said grooves and extending substantially half the length of said other of said grooves, means for maintaining said piston segc ments against rotation with said rotor while permitting lateral oscillation of said segments, two diametrically opposite inlet recesses within said housing adjacent said spherical surface of said rotor, and two diametrically opposite discharge recesses within said housing adjacent said spherical surface of said rotor, all of said recesses extending transversely with respect to said grooves, each of said inlet recesses being circumferentially spaced from the corresponding one of said discharge recesses and being disposed on the opposite side from said corresponding one of said discharge recesses with respect to a plane extending between the ends of said segments and along the axis of said rotor, one of said inlet recesses and one of said discharge recesses communicating with each of said grooves, said one of said grooves being in communication with one of said inlet recesses adjacent one end of said second segment and being in communication with one of said discharge recesses adjacent the other end of said second segment, said other of said grooves being in communication with the other of said inlet recesses adjacent one end of said first segment and being in communication with the other of said discharge recesses adjacent the other end of said first segment. I

FLOYD M. KIRKPATRICK.

No references cited, 

